Prevented from reaching the email to wrong address

Since the Undo Send feature is part of Gmail Labs, you’ll have to navigate to the Gmail Labs page to activate it.

Sing in Gmail and look in the top-right corner of the page. 
click on the "Stettings"

a) Click on the Labs tab.
b) Enable “Undo Send” and Save Your Change.

 Save Changes. 

Customize Undo Send’s Duration

By default, Gmail gives you a 10-second window of time in which you may undo a sent e-mail. You can change that to five, 20 or 30 seconds.

 by going to Settings and finding the Undo Send section inside the “General” tab.

There you can enable or disable Undo Send and change the duration with a drop-down selection box as pictured above.

Now that Undo Send is enabled, it works each time you send a new e-mail. You don’t have to do anything unusual beforehand to make it possible to use Undo Send with that e-mail.

create a new free gmail account

Signing in with multiple Gmail addresses